DE102015007655A1 - Filter element and filter assembly - Google Patents

Abstract

A filter element (1) having an end plate (3), a filter medium (5) attached to the end plate (3), the filter medium (5) being fixed to the end plate (3) by means of a polyurethane material (12), and an annular one Sealing element (13), which is made of a thermoplastic elastomer and which is arranged at an outflow opening (14) of the end plate (3).

Description

Technical area

The present invention relates to a filter element and a filter assembly with such a filter element.

State of the art

Filter elements, such as air filter elements, may include two end plates and an endless bellows located between the two end plates. In this case, a star-shaped folded filter medium is created in the manner of a cylinder and the end faces of the cylinder are closed with the end plates. The fluid to be filtered, such as air, enters the filter element through the filter medium and out of the filter element again through a discharge opening provided in an end plate. For sealing the filter element with respect to a resource connection, a sealing element may be provided.

The EP 0 945 160 A1 describes a polyamide endplate for a filter element with a radially acting seal made of rubber. For connecting a filter medium with the end plate this is melted and pressed the filter medium in the end plate.

Disclosure of the invention

Against this background, the present invention has for its object to provide an improved filter element.

Accordingly, a filter element with an end plate, a filter medium attached to the end plate, wherein the filter medium is fixed by means of a polyurethane material to the end plate, and an annular sealing element is proposed. The annular sealing element is made of a thermoplastic elastomer and arranged at an outflow opening of the end plate.

The fact that the annular sealing element is made of a thermoplastic elastomer, can be generated by its processability in an injection molding process a geometrically very precisely definable sealing contour. Since the filter medium for joining with the end plate is not fused with this, but is connected by means of the polyurethane material with this, the filter element can be made particularly simple. On a melting of the end plate can be omitted. Furthermore, a reliable end-side sealing of the filter medium is achieved by the use of the polyurethane material.

The filter element is in particular an air filter element. The filter element may have two end plates, between which the filter medium is arranged. The discharge opening is provided on a first end disk. A second end disk preferably has no outflow opening and closes the filter medium in a fluid-tight manner on the end side. The annular sealing element is preferably arranged in the outflow opening, in particular on an inner wall of the outflow opening. In particular, the annular sealing element completely circulates the outflow opening. Preferably, the annular sealing element is permanently connected to the end plate. The polyurethane material for bonding, in particular for bonding, the end plate with the filter medium preferably forms a closed ring.

The polyurethane material for fixing the filter medium to the end plate is in particular a material which is produced by mixing several chemical components together and then reacting with one another. In this case, the polyurethane material foams and crosslinks. Polyurethane materials are understood in particular to be plastics which arise from a polyaddition reaction of dialcohols or polyols with polyisocyanates. Such polyurethane materials are in particular pourable without pressure. The polyurethane material can therefore be referred to as, in particular pressure-free, pourable polyurethane material. In contrast, thermoplastic elastomers (TPE) and in particular thermoplastic polyurethanes (TPU) are materials which behave at room temperature comparable to conventional elastomers, such as the previously mentioned castable polyurethane material, but can be plastically deformed under heat input and thus a show thermoplastic behavior. Thermoplastic elastomers, in particular thermoplastic polyurethanes, can therefore be processed in a plastic injection molding process or a plastic extrusion process, in contrast to the previously mentioned castable polyurethane materials. Therefore, unlike castable polyurethane materials, such thermoplastic elastomers may also be referred to as injection moldable elastomers.

In embodiments, the end plate is cup-shaped, in particular U-shaped in cross-section, and comprises an inner wall and an outer wall, wherein a part of the filter medium and the polyurethane material between the inner wall and the outer wall are arranged. In particular, an end portion of the filter medium is arranged in the cup-shaped end disk. Furthermore, a support structure arranged within the filter medium can also be arranged in the end disk. The polyurethane material is in particular depressurized in cast the end plate and connects the end plate with the filter medium and the support structure. The end plate serves as the casting element remaining on the filter element for the polyurethane material. Preferably, the filter element in addition to the first end plate with the discharge opening and the second, preferably closed, end plate, wherein the filter medium is arranged between the end plates. The second end plate is preferably made of a castable polyurethane material. In particular, the second end plate is pressure-less cast on the filter medium and / or on the support structure.

In further embodiments, the inner wall and outer wall are cylindrical and coaxial with each other, wherein the inner wall is disposed within the outer wall. Preferably, the inner wall and the outer wall are tubular. The inner wall and the outer wall are connected to each other in particular by means of a base portion.

In further embodiments, the inner wall is higher in a longitudinal direction of the filter element than the outer wall. As a result, the polyurethane material is prevented from foaming into an interior space of the filter element encompassed by the support structure during foaming. In particular, because the outer wall is lower than the inner wall, the polyurethane material can only run outward. As a result, it is reliably prevented that a sealing of the filter element takes place with respect to a resource connection with the aid of the polyurethane material.

In further embodiments, the annular sealing element is adapted to radially seal the filter element with respect to a resource connection. The resource port may be tubular. The resource port may be part of a filter housing of the filter element. The seal against the resource connection is made exclusively by means of the annular sealing element. The annular sealing element may optionally also be suitable for axial sealing.

In further embodiments, the annular sealing element comprises at least one foldable sealing lip. Preferably, the sealing element comprises a plurality of sealing lips. For example, the sealing element may comprise three sealing lips. The sealing lips can be folded over or folded down. In particular, the sealing lips can be folded over when the operating medium connection is introduced into the outflow opening. The annular sealing element and in particular the sealing lips are elastically deformable.

In further embodiments, the at least one sealing lip comprises an undercut. As a result, the sealing effect can be improved. In particular, such an undercut can only be produced in a plastic injection molding process.

In further embodiments, the annular sealing element is molded onto the end plate in a plastic injection molding process. By using a plastic injection molding process, the annular sealing element can be produced geometrically very accurately with low tolerances. Preferably, the annular sealing element can also be produced in large quantities. Preferably, the end plate with the annular sealing element is a two-component injection-molded component. In particular, the annular sealing element is molded on the inside of the outflow opening. Alternatively, the annular sealing element can be attached to the end plate even after the manufacture thereof. For example, the annular sealing element can be knotted on or in the end plate, in particular fused, welded or glued to it. Furthermore, the annular sealing element may be formed of an extruded profile which is formed into a closed ring. The annular sealing element is preferably made of a TPU. The end plate may be made of polyamide (PA) or polybutylene terephthalate (PBT). The PA or PBT may be fiber filled, in particular filled with glass fiber. As a result, a high strength is achieved.

In further embodiments, the annular sealing element comprises spacer elements which extend beyond the end disk in a longitudinal direction of the filter element. The longitudinal direction can be oriented from the second end disk in the direction of the first end disk or vice versa. In particular, the spacer elements extend out of an end face of the end disk, which faces away from the filter medium. With the help of the spacer elements, the filter element can be positioned axially in a filter housing. The spacer elements are preferably formed in one piece with the annular sealing element.

Furthermore, a filter arrangement with such a filter element and a filter housing for receiving the filter element is proposed. The filter housing may have a resource port. The filter housing may further comprise a receiving portion for receiving the filter element and a lid for closing the receiving portion. By removing the lid, the filter element can be replaced.

Further possible implementations of the invention also include combinations which have not been explicitly mentioned above of the following Embodiments described features or method steps. The skilled person will also add individual aspects as improvements or additions to the respective basic form of the invention.

Further embodiments of the invention are the subject of the dependent claims and the embodiments of the invention described below. Furthermore, the invention will be explained in more detail by means of embodiments with reference to the accompanying figures.

Brief description of the drawings

It shows:

1 a schematic perspective view of an embodiment of a filter element;

2 FIG. 2: shows a schematic partial sectional view of an embodiment of a filter arrangement with a filter element according to FIG 1 ; and

3 a schematic partial sectional view of the filter element according to 1 ,

In the figures, identical or functionally identical elements, unless otherwise indicated, have been given the same reference numerals.

Embodiment (s) of the invention

1 shows a schematic perspective view of an embodiment of a filter element 1 , 2 shows a schematic partial sectional view of an embodiment of a filter assembly 2 with such a filter element 1 , 3 shows a schematic partial sectional view of the filter element 1 , The following will be on 1 to 3 simultaneously referred to.

The filter element 1 may be suitable for filtering water, urea solution, air, oil, or fuels such as diesel fuel, kerosene or gasoline. In particular, the filter element finds 1 in motor vehicles, heavy goods vehicles, construction vehicles, vessels, rail vehicles or aircraft. Furthermore, the filter element 1 find application in structures. The filter element 1 is in particular an air filter element and is suitable for filtering combustion air of an internal combustion engine.

The filter element 1 includes a first or upper end plate 3 and a second or lower end disc 4 , Between the two end discs 3 . 4 is a flat filter medium 5 intended. The filter medium 5 may be a filter body of flat and zigzag folded filter material. The zigzag-shaped filter material forms the filter medium 5 as a star-shaped endless bellows, which essentially forms a cylindrical surface. The filter medium 5 can from the outside with a network 6 be surrounded. The network 6 For example, it can catch coarse dirt particles such as leaves or grasses. Furthermore, the network protects 6 when replacing the filter element 1 the filter medium 5 from damage. The network 6 can also have a supporting effect.

The filter medium 5 is for example a filter fabric, a Filtergelege or a filter fleece. In particular, the filter medium 5 be prepared in a spunbond or meltblown process. Next, the filter medium 5 felted or needled. The filter medium 5 may comprise natural fibers, such as cellulose or cotton, or synthetic fibers, for example of polyester, polyvinyl sulfite or polytetrafluoroethylene. Fibers of the filter medium 5 may be oriented in, skewed and / or transversely to the machine direction during processing.

The filter medium 5 can also from the inside of a fluid-permeable support structure 7 to be supported. The support structure 7 may be tubular. Preferably, the support structure 7 a grid. The support structure 7 may collapse the filter medium 5 prevent. The support structure 7 can also be designed as a central tube or winding core. The filter medium 5 may alternatively have no zigzag folding, but be flat or flat and on the support structure 7 be wound up.

The filter medium 5 is fluid-tight with the end discs 3 . 4 , connected. The second end disk 4 is preferably made of a polyurethane material and to the filter medium 5 a glove. The one for making the end disc 4 used polyurethane material is preferably elastically deformable and may have an internal foam structure. Preferably, the for producing the end plate 4 used polyurethane material produced by mixing various chemical components that react and crosslink after mixing with each other.

Polyurethane materials are understood in particular to be plastics which arise from a polyaddition reaction of dialcohols or polyols with polyisocyanates. Characteristic of polyurethane materials is a urethane group. Such polyurethane materials are pourable without pressure. The one for the second end disc 4 used polyurethane material can therefore be referred to as, in particular pressure-free, pourable polyurethane material. In contrast, thermoplastic elastomers, and in particular thermoplastic polyurethanes, are materials which, at room temperature, are comparable to conventional elastomers, such as those described above behave said pourable polyurethane material, but can be plastically deformed under heat and thus show a thermoplastic behavior. In particular, thermoplastic elastomers, in particular thermoplastic polyurethanes, in contrast to the previously mentioned castable polyurethane materials in a plastic injection molding process can be processed. Therefore, such thermoplastic elastomers may also be referred to as injection moldable elastomers.

In particular, the end plate 4 depressurized to the filter medium 5 a glove. In this case, the material of the end plate 4 lather. To form the end plate 4 The polyurethane material is poured without pressure in a low-cost mold. Subsequently, the filter medium 5 used in the liquid polyurethane material. In particular, the support structure is 7 end with end plate material 4 cast around. Alternatively, the end disc 4 with a suitable material, such as PA, in a plastic injection molding process to the filter medium 5 be sprayed. Also a closure element 8th that the filter element 1 terminates at the end, can with the material of the end plate 4 be infused, leaving the end disc 4 , the support structure 7 , the filter medium 5 , and the closure element 8th form a cohesively connected unit. At one of the filter medium 5 opposite end face 9 the end plate 4 are spacers 10 provided, the axial spacing and / or the positioning of the filter element 1 in a filter housing 11 serve. The spacers 10 can be material integral with the end plate 4 be connected. There may be three or more such spacers 10 be provided.

At the first end disk 3 , which is preferably made of a thermoplastic material in an injection molding process, is the filter medium 5 with the help of a castable polyurethane material 12 attached. For attaching the filter medium 5 at the end disc 3 is preferably the same or a chemically similar material as that for the production of the second or lower end plate 4 used, can be used. That is the polyurethane material 12 is made by mixing several chemical components and is not processable in a plastic injection molding process.

The filter element 1 and in particular the end plate 3 further comprises an annular sealing element 13 which is made of a TPE. In particular, the annular sealing element 13 made of a TPU. The annular sealing element 13 is on or in an outflow opening 14 the end plate 3 arranged. In particular, the annular sealing element 13 in a two-component plastic injection molding process to the end plate 3 be sprayed. The end disc 3 is preferably made of a PA. In particular, the end plate 3 be made of a fiber reinforced PA. For example, the material PA6-GF30 can be used. Alternatively, as a material for the end plate 3 a PBT, in particular a fiber-reinforced PBT, such as the material PBT GF30 application find.

The annular sealing element 13 is set to the filter element 1 opposite a, in particular tubular, resource connection 15 seal radially. Optionally, the annular sealing element 13 also be adapted to the filter element 1 opposite the equipment connection 15 axially sealed. The resource connection 15 can be part of the filter housing 11 be. The filter housing 11 may have a lid, not shown, through which the filter element 1 is interchangeable. The filter arrangement 2 includes the filter element 1 and the filter housing 11 with the equipment connection 15 ,

As the 2 and 3 show is the first end disk 3 cup-shaped and in particular U-shaped in cross-section. The end disc 3 includes an inner wall 16 , an exterior wall 17 and one the inner wall 16 with the outer wall 17 connecting base section 18 , The base section 18 is ring-shaped. Part of the filter medium 5 and the polyurethane material 12 are between the inner wall 16 and the outer wall 17 arranged. The inner wall 16 and the outer wall 17 are cylindrical, in particular tubular, and arranged coaxially with each other, wherein the inner wall 16 inside the outer wall 17 is arranged.

In a longitudinal direction LR of the filter element 1 coming from the second end disc 4 in the direction of the first end disk 3 or may be oriented the other way around, is the inner wall 16 the end plate 3 higher than the outer wall 17 , For example, the inner wall 16 a height h ₁₆ and the outer wall 17 a height h ₁₇ on. The height h ₁₆ is greater than the height h ₁₇ . The fact that the height h _{16 is} greater than the height h ₁₇ , prevents the polyurethane material 12 when pouring into the end plate 3 over the inner wall 16 in one of the support structure 7 circumscribed interior 19 of the filter element 1 into running. This will ensure that the radial seal of the filter element 1 exclusively with the aid of the annular sealing element 13 and not with the help of polyurethane material 12 he follows. Between the inner wall 16 and the outer wall 17 is also the support structure 7 arranged. In particular, the support structure 7 between the inner wall 16 and the filter medium 5 arranged.

For connecting the end plate 3 with the filter medium 5 and the support structure 7 becomes the polyurethane material 12 in the end disc 3 cast, which serves as a mold. Subsequently, the support structure 7 and the filter medium 5 in the cup-shaped end disc 3 set. After foaming the polyurethane material 12 and the crosslinking of the same are the filter medium 5 and the support structure 7 firmly with the end disc 3 connected. In particular, the polyurethane material seals 12 the filter medium 5 front side fluid-tight.

As 3 further shows, has the annular sealing element 13 at least one sealing lip 20 to 22 on. The number of sealing lips 20 to 22 is arbitrary. There can be three sealing lips 20 to 22 be provided. The sealing lips 20 to 22 are when inserting the equipment connection 15 in the discharge opening 14 foldable or foldable. As a result, a particularly good radial sealing effect is achieved. The sealing lips 20 to 22 may in particular include an undercut. Such an undercut can not be produced with a castable polyurethane material. By using a thermoplastic elastomer for the annular sealing element 13 can be produced particularly well undercuts in the production of the same in a plastic injection molding process. Through the undercuts, the sealing effect of the annular sealing element 13 be further improved. The geometry of the sealing lips 20 to 22 is geometrically freely configurable due to the use of the thermoplastic elastomer.

The annular sealing element 13 further comprises in the longitudinal direction LR of the filter element 1 over the end disc 3 and in particular via a front side of the end plate 3 extending spacers 23 to 25 , With the help of elastically deformable spacers 23 to 25 is the filter element 1 axially in the filter housing 11 positionable.

The filter element 1 shows how 1 shows a raw side RO and a clean side RL. To be cleaned fluid, such as air, passes from the raw side RO through the filter medium 5 in the from the support structure 7 limited interior 19 of the filter element 1 a, wherein the fluid to be purified from the filter medium 5 is filtered. This supports the support structure 7 the filter medium 5 such that it does not collapse. From the interior 19 the cleaned fluid is directed towards the clean side RL via the discharge opening 14 from the filter element 1 dissipated.

Characterized in that the annular sealing element 13 is made of a TPE, a geometrically exactly definable sealing contour can be produced. In particular, it is through the use of an injection molding process for producing the annular sealing element 13 the geometry of the annular sealing element 13 much better definable compared to a castable polyurethane material. Furthermore, in the plastic injection molding process, a plurality of clearly defined sealing lips 20 to 22 can be generated, whereby an improved sealing performance is achieved. Furthermore, on the sealing lips 20 to 22 Undercuts also possible, which further improve the sealing performance and a tight fit of the annular sealing element 13 to the equipment connection 15 always reliable.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0945160 A1 [0003]

Claims (10)

Filter element ( 1 ) with an end plate ( 3 ), one at the end disc ( 3 ) attached filter medium ( 5 ), whereby the filter medium ( 5 ) using a polyurethane material ( 12 ) at the end plate ( 3 ), and an annular sealing element ( 13 ), which is made of a thermoplastic elastomer and at an outflow opening ( 14 ) of the end plate ( 3 ) is arranged. Filter element according to claim 1, wherein the end plate ( 3 ) cup-shaped, in particular U-shaped in cross-section, and an inner wall ( 16 ) and an outer wall ( 17 ), wherein a part of the filter medium ( 5 ) and the polyurethane material ( 12 ) between the inner wall ( 16 ) and the outer wall ( 17 ) are arranged. Filter element according to claim 2, wherein the inner wall ( 16 ) and the outer wall ( 17 ) are arranged cylindrical and coaxial with each other and wherein the inner wall ( 16 ) within the outer wall ( 17 ) is arranged. Filter element according to claim 2 or 3, wherein the inner wall ( 16 ) in a longitudinal direction (LR) of the filter element (FIG. 1 ) higher than the outer wall ( 17 ). Filter element according to one of claims 1-4, wherein the annular sealing element ( 13 ) is adapted to the filter element ( 1 ) against a resource connection ( 15 ) radially seal. Filter element according to one of claims 1-5, wherein the annular sealing element ( 13 ) at least one foldable sealing lip ( 20 - 22 ). Filter element according to claim 6, wherein the at least one sealing lip ( 20 - 22 ) comprises an undercut. Filter element according to one of claims 1-7, wherein the annular sealing element ( 13 ) in a plastic injection molding process to the end plate ( 3 ) is injected. Filter element according to one of claims 1-8, wherein the annular sealing element ( 13 ) in a longitudinal direction (LR) of the filter element ( 1 ) over the end plate ( 3 ) extending spacers ( 23 - 25 ). Filter arrangement ( 2 ) with a filter element ( 1 ) according to any one of claims 1-9 and a filter housing ( 11 ) for receiving the filter element ( 1 ).

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